Three types of back saw: the dozuki, gent's saw, and tenon saw.
A back saw is a saw that has a stiffening rib of steel or brass fixed to the edge of the blade opposite to the cutting edge. This makes the back saw particulary well-suited to jobs that demand good control and precise cutting. Such jobs include cutting dovetails, miters, or tenons in cabinetry and joinery. Backsaws usually have closely-spaced teeth, often with little or no set. Because the stiffener is thicker than the blade, backsaws are limited in the depth to which they can cut.
A typical back saw blade is 8 to 14 inches long with 11 to 14 teeth per inch (tpi).